Kolkata: The West Bengal Commission for Women on Sunday said the police did not act even though the convent where a 70-year-old nun was gang-raped had been receiving threats from some quarters.

The nun was brutalised by a gang of bandits inside the Convent of Jesus and Mary in Ranaghat, some 80 km from Kolkata, early Saturday.

Commission chairperson Sunanda Mukherjee during the day visited the convent and met the survivor who is undergoing treatment at a hospital.

"In November last year a student of the school was suspended on disciplinary ground following which some of the teachers received threats which was reported to the sub divisional officer," said Mukherjee.

"A week back some miscreants entered the school and threatened one of the sisters saying `I will kill you`. A police complaint in this regard was promptly lodged but no action was taken. There is no doubt about police inaction in this matter too," said Mukherjee.

She said the commission was looking into the matter and would recommend steps against police officers found guilty of dereliction of duty.

Strongly condemning the incident, Chief Minister Mamata Banerjee on Saturday ordered the Criminal Investigation Department (CID) to probe the matter and promised "swift" and "strongest action" against the culprits.

While several people have been detained for questioning, the police are yet to arrest any of the culprits whose snapshots have been published.

The police have also announced a reward of Rs.1 lakh for providing information about the perpetrators.

Earlier in the day, Governor K. N. Tripathi promised action and urged the general public to help the police in nabbing the criminals.

"The state government will take strict action in this matter," Tripathi told the media.

"The administration will surely apprehend the culprits and punish them. I feel people should also come forward to help nab the culprits," he said.